The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Jan. 04, 2005
Filed:
Jun. 04, 2001
Jeffrey M. Dicarlo, Sunnyvale, CA (US);
Peter B. Catrysse, Palo Alto, CA (US);
Feng Xiao, Stanford, CA (US);
Brian A. Wandell, Menlo Park, CA (US);
Jeffrey M. Dicarlo, Sunnyvale, CA (US);
Peter B. Catrysse, Palo Alto, CA (US);
Feng Xiao, Stanford, CA (US);
Brian A. Wandell, Menlo Park, CA (US);
The Board of Trustees of the Leland Stanford Junior University, Stanford, CA (US);
Abstract
Color balancing algorithms for digital image processing require an accurate estimate of the physical properties of the ambient scene illuminant, particularly its spectral power distribution. An active imaging method and apparatus estimate these properties by emitting modulated light with a known spectral power distribution into a region of a scene. Backscattered light is detected and demodulated to separate output representing active emitter light from output representing ambient illuminant light. Using the emitter-related detector output and the known emitter spectral power distribution, the surface spectral reflectance function of the illuminated scene region can be computed. Subsequently, the spectral power distribution of the ambient scene illuminant can be computed from the surface reflectance function and the illuminant-related output of the detector. The estimated spectral power distribution can be used in standard color balancing algorithms for digital or film images.